2002-09-17 23:50:03 +00:00
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/* Wrapper around clone system call. PowerPC64 version.
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2021-01-02 19:32:25 +00:00
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Copyright (C) 1997-2021 Free Software Foundation, Inc.
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2002-09-17 23:50:03 +00:00
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This file is part of the GNU C Library.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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2012-02-09 23:18:22 +00:00
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License along with the GNU C Library; if not, see
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Prefer https to http for gnu.org and fsf.org URLs
Also, change sources.redhat.com to sourceware.org.
This patch was automatically generated by running the following shell
script, which uses GNU sed, and which avoids modifying files imported
from upstream:
sed -ri '
s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g
s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g
' \
$(find $(git ls-files) -prune -type f \
! -name '*.po' \
! -name 'ChangeLog*' \
! -path COPYING ! -path COPYING.LIB \
! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \
! -path manual/texinfo.tex ! -path scripts/config.guess \
! -path scripts/config.sub ! -path scripts/install-sh \
! -path scripts/mkinstalldirs ! -path scripts/move-if-change \
! -path INSTALL ! -path locale/programs/charmap-kw.h \
! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \
! '(' -name configure \
-execdir test -f configure.ac -o -f configure.in ';' ')' \
! '(' -name preconfigure \
-execdir test -f preconfigure.ac ';' ')' \
-print)
and then by running 'make dist-prepare' to regenerate files built
from the altered files, and then executing the following to cleanup:
chmod a+x sysdeps/unix/sysv/linux/riscv/configure
# Omit irrelevant whitespace and comment-only changes,
# perhaps from a slightly-different Autoconf version.
git checkout -f \
sysdeps/csky/configure \
sysdeps/hppa/configure \
sysdeps/riscv/configure \
sysdeps/unix/sysv/linux/csky/configure
# Omit changes that caused a pre-commit check to fail like this:
# remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines
git checkout -f \
sysdeps/powerpc/powerpc64/ppc-mcount.S \
sysdeps/unix/sysv/linux/s390/s390-64/syscall.S
# Omit change that caused a pre-commit check to fail like this:
# remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline
git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
2019-09-07 05:40:42 +00:00
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<https://www.gnu.org/licenses/>. */
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2002-09-17 23:50:03 +00:00
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#include <sysdep.h>
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#define _ERRNO_H 1
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#include <bits/errno.h>
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/* This is the only really unusual system call in PPC linux, but not
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because of any weirdness in the system call itself; because of
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all the freaky stuff we have to do to make the call useful. */
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/* int [r3] clone(int (*fn)(void *arg) [r3], void *child_stack [r4],
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2003-03-10 21:04:29 +00:00
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int flags [r5], void *arg [r6], void *parent_tid [r7],
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void *tls [r8], void *child_tid [r9]); */
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2002-09-17 23:50:03 +00:00
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2013-03-06 00:10:21 +00:00
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ENTRY (__clone)
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2004-12-14 21:25:41 +00:00
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CALL_MCOUNT 7
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2002-09-17 23:50:03 +00:00
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/* Check for child_stack == NULL || fn == NULL. */
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cmpdi cr0,r4,0
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2004-12-15 20:37:06 +00:00
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cmpdi cr1,r3,0
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2002-09-17 23:50:03 +00:00
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cror cr0*4+eq,cr1*4+eq,cr0*4+eq
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beq- cr0,L(badargs)
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PowerPC64 ELFv2 ABI 4/6: Stack frame layout changes
This updates glibc for the changes in the ELFv2 relating to the
stack frame layout. These are described in more detail here:
http://gcc.gnu.org/ml/gcc-patches/2013-11/msg01149.html
http://gcc.gnu.org/ml/gcc-patches/2013-11/msg01146.html
Specifically, the "compiler and linker doublewords" were removed,
which has the effect that the save slot for the TOC register is
now at offset 24 rather than 40 to the stack pointer.
In addition, a function may now no longer necessarily assume that
its caller has set up a 64-byte register save area its use.
To address the first change, the patch goes through all assembler
files and replaces immediate offsets in instructions accessing the
ABI-defined stack slots by symbolic offsets. Those already were
defined in ucontext_i.sym and used in some of the context routines,
but that doesn't really seem like the right place for those defines.
The patch instead defines those symbolic offsets in sysdeps.h,
in two variants for the old and new ABI, and uses them systematically
in all assembler files, not just the context routines.
The second change only affected a few assembler files that used
the save area to temporarily store some registers. In those
cases where this happens within a leaf function, this patch
changes the code to store those registers to the "red zone"
below the stack pointer. Otherwise, the functions already allocate
a stack frame, and the patch changes them to add extra space in
these frames as temporary space for the ELFv2 ABI.
2013-12-04 12:55:03 +00:00
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/* Save some regs in the "red zone". */
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2021-04-09 17:47:27 +00:00
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#ifdef USE_PPC_SCV
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2020-12-03 17:15:28 +00:00
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std r28,-32(r1)
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2021-04-09 17:47:27 +00:00
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cfi_offset(r28,-32)
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#endif
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PowerPC64 ELFv2 ABI 4/6: Stack frame layout changes
This updates glibc for the changes in the ELFv2 relating to the
stack frame layout. These are described in more detail here:
http://gcc.gnu.org/ml/gcc-patches/2013-11/msg01149.html
http://gcc.gnu.org/ml/gcc-patches/2013-11/msg01146.html
Specifically, the "compiler and linker doublewords" were removed,
which has the effect that the save slot for the TOC register is
now at offset 24 rather than 40 to the stack pointer.
In addition, a function may now no longer necessarily assume that
its caller has set up a 64-byte register save area its use.
To address the first change, the patch goes through all assembler
files and replaces immediate offsets in instructions accessing the
ABI-defined stack slots by symbolic offsets. Those already were
defined in ucontext_i.sym and used in some of the context routines,
but that doesn't really seem like the right place for those defines.
The patch instead defines those symbolic offsets in sysdeps.h,
in two variants for the old and new ABI, and uses them systematically
in all assembler files, not just the context routines.
The second change only affected a few assembler files that used
the save area to temporarily store some registers. In those
cases where this happens within a leaf function, this patch
changes the code to store those registers to the "red zone"
below the stack pointer. Otherwise, the functions already allocate
a stack frame, and the patch changes them to add extra space in
these frames as temporary space for the ELFv2 ABI.
2013-12-04 12:55:03 +00:00
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std r29,-24(r1)
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std r30,-16(r1)
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std r31,-8(r1)
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cfi_offset(r29,-24)
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cfi_offset(r30,-16)
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cfi_offset(r31,-8)
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2002-09-17 23:50:03 +00:00
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/* Set up stack frame for child. */
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clrrdi r4,r4,4
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li r0,0
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PowerPC64 ELFv2 ABI 4/6: Stack frame layout changes
This updates glibc for the changes in the ELFv2 relating to the
stack frame layout. These are described in more detail here:
http://gcc.gnu.org/ml/gcc-patches/2013-11/msg01149.html
http://gcc.gnu.org/ml/gcc-patches/2013-11/msg01146.html
Specifically, the "compiler and linker doublewords" were removed,
which has the effect that the save slot for the TOC register is
now at offset 24 rather than 40 to the stack pointer.
In addition, a function may now no longer necessarily assume that
its caller has set up a 64-byte register save area its use.
To address the first change, the patch goes through all assembler
files and replaces immediate offsets in instructions accessing the
ABI-defined stack slots by symbolic offsets. Those already were
defined in ucontext_i.sym and used in some of the context routines,
but that doesn't really seem like the right place for those defines.
The patch instead defines those symbolic offsets in sysdeps.h,
in two variants for the old and new ABI, and uses them systematically
in all assembler files, not just the context routines.
The second change only affected a few assembler files that used
the save area to temporarily store some registers. In those
cases where this happens within a leaf function, this patch
changes the code to store those registers to the "red zone"
below the stack pointer. Otherwise, the functions already allocate
a stack frame, and the patch changes them to add extra space in
these frames as temporary space for the ELFv2 ABI.
2013-12-04 12:55:03 +00:00
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stdu r0,-FRAME_MIN_SIZE_PARM(r4)
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2002-09-17 23:50:03 +00:00
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/* Save fn, args, stack across syscall. */
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2010-08-12 16:19:19 +00:00
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mr r30,r3 /* Function in r30. */
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mr r29,r5 /* Flags in r29. */
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2002-09-17 23:50:03 +00:00
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mr r31,r6 /* Argument in r31. */
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2010-08-12 16:19:19 +00:00
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/* 'flags' argument is first parameter to clone syscall.
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Second is the stack pointer, already in r4. */
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2002-09-17 23:50:03 +00:00
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mr r3,r5
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2014-05-21 01:31:04 +00:00
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/* Move the parent_tid, child_tid and tls arguments. */
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2003-03-10 21:04:29 +00:00
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mr r5,r7
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mr r6,r8
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mr r7,r9
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2002-09-17 23:50:03 +00:00
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2006-04-04 07:01:16 +00:00
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/* End FDE now, because in the child the unwind info will be
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wrong. */
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cfi_endproc
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2002-09-17 23:50:03 +00:00
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/* Do the call. */
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powerpc: Runtime selection between sc and scv for syscalls
Linux kernel v5.9 added support for system calls using the scv
instruction for POWER9 and later. The new codepath provides better
performance (see below) if compared to using sc. For the
foreseeable future, both sc and scv mechanisms will co-exist, so this
patch enables glibc to do a runtime check and use scv when it is
available.
Before issuing the system call to the kernel, we check hwcap2 in the TCB
for PPC_FEATURE2_SCV to see if scv is supported by the kernel. If not,
we fallback to sc and keep the old behavior.
The kernel implements a different error return convention for scv, so
when returning from a system call we need to handle the return value
differently depending on the instruction we used to enter the kernel.
For syscalls implemented in ASM, entry and exit are implemented by
different macros (PSEUDO and PSEUDO_RET, resp.), which may be used in
sequence (e.g. for templated syscalls) or with other instructions in
between (e.g. clone). To avoid accessing the TCB a second time on
PSEUDO_RET to check which instruction we used, the value read from
hwcap2 is cached on a non-volatile register.
This is not needed when using INTERNAL_SYSCALL macro, since entry and
exit are bundled into the same inline asm directive.
The dynamic loader may issue syscalls before the TCB has been setup
so it always uses sc with no extra checks. For the static case, there
is no compile-time way to determine if we are inside startup code,
so we also check the value of the thread pointer before effectively
accessing the TCB. For such situations in which the availability of
scv cannot be determined, sc is always used.
Support for scv in syscalls implemented in their own ASM file (clone and
vfork) will be added later. For now simply use sc as before.
Average performance over 1M calls for each syscall "type":
- stat: C wrapper calling INTERNAL_SYSCALL
- getpid: templated ASM syscall
- syscall: call to gettid using syscall function
Standard:
stat : 1.573445 us / ~3619 cycles
getpid : 0.164986 us / ~379 cycles
syscall : 0.162743 us / ~374 cycles
With scv:
stat : 1.537049 us / ~3535 cycles <~ -84 cycles / -2.32%
getpid : 0.109923 us / ~253 cycles <~ -126 cycles / -33.25%
syscall : 0.116410 us / ~268 cycles <~ -106 cycles / -28.34%
Tested on powerpc, powerpc64, powerpc64le (with and without scv)
Tested-by: Lucas A. M. Magalhães <lamm@linux.ibm.com>
Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
2020-12-03 17:15:27 +00:00
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li r0,SYS_ify(clone)
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2021-04-09 17:47:27 +00:00
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#ifdef USE_PPC_SCV
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2020-12-03 17:15:28 +00:00
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CHECK_SCV_SUPPORT r28 0f
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/* This is equivalent to DO_CALL_SCV, but we cannot use the macro here
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because it uses CFI directives and we just called cfi_endproc. */
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mflr r9
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std r9,FRAME_LR_SAVE(r1)
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2021-01-21 17:16:49 +00:00
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.machine "push"
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.machine "power9"
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2020-12-03 17:15:28 +00:00
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scv 0
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2021-01-21 17:16:49 +00:00
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.machine "pop"
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2020-12-03 17:15:28 +00:00
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ld r9,FRAME_LR_SAVE(r1)
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mtlr r9
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/* Check for child process. */
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/* When using scv, error is indicated by negative r3. */
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cmpdi cr1,r3,0
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b 1f
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2021-04-09 17:47:27 +00:00
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#endif /* USE_PPC_SCV */
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2020-12-03 17:15:28 +00:00
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0: DO_CALL_SC
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2002-09-17 23:50:03 +00:00
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/* Check for child process. */
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2020-12-03 17:15:28 +00:00
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/* With sc, error is indicated by cr0.SO. */
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2002-09-17 23:50:03 +00:00
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cmpdi cr1,r3,0
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crandc cr1*4+eq,cr1*4+eq,cr0*4+so
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2020-12-03 17:15:28 +00:00
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1:
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2002-09-17 23:50:03 +00:00
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bne- cr1,L(parent) /* The '-' is to minimise the race. */
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PowerPC64 ELFv2 ABI 4/6: Stack frame layout changes
This updates glibc for the changes in the ELFv2 relating to the
stack frame layout. These are described in more detail here:
http://gcc.gnu.org/ml/gcc-patches/2013-11/msg01149.html
http://gcc.gnu.org/ml/gcc-patches/2013-11/msg01146.html
Specifically, the "compiler and linker doublewords" were removed,
which has the effect that the save slot for the TOC register is
now at offset 24 rather than 40 to the stack pointer.
In addition, a function may now no longer necessarily assume that
its caller has set up a 64-byte register save area its use.
To address the first change, the patch goes through all assembler
files and replaces immediate offsets in instructions accessing the
ABI-defined stack slots by symbolic offsets. Those already were
defined in ucontext_i.sym and used in some of the context routines,
but that doesn't really seem like the right place for those defines.
The patch instead defines those symbolic offsets in sysdeps.h,
in two variants for the old and new ABI, and uses them systematically
in all assembler files, not just the context routines.
The second change only affected a few assembler files that used
the save area to temporarily store some registers. In those
cases where this happens within a leaf function, this patch
changes the code to store those registers to the "red zone"
below the stack pointer. Otherwise, the functions already allocate
a stack frame, and the patch changes them to add extra space in
these frames as temporary space for the ELFv2 ABI.
2013-12-04 12:55:03 +00:00
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std r2,FRAME_TOC_SAVE(r1)
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2002-09-17 23:50:03 +00:00
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/* Call procedure. */
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2013-12-04 12:49:15 +00:00
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PPC64_LOAD_FUNCPTR r30
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2002-09-17 23:50:03 +00:00
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mr r3,r31
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bctrl
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PowerPC64 ELFv2 ABI 4/6: Stack frame layout changes
This updates glibc for the changes in the ELFv2 relating to the
stack frame layout. These are described in more detail here:
http://gcc.gnu.org/ml/gcc-patches/2013-11/msg01149.html
http://gcc.gnu.org/ml/gcc-patches/2013-11/msg01146.html
Specifically, the "compiler and linker doublewords" were removed,
which has the effect that the save slot for the TOC register is
now at offset 24 rather than 40 to the stack pointer.
In addition, a function may now no longer necessarily assume that
its caller has set up a 64-byte register save area its use.
To address the first change, the patch goes through all assembler
files and replaces immediate offsets in instructions accessing the
ABI-defined stack slots by symbolic offsets. Those already were
defined in ucontext_i.sym and used in some of the context routines,
but that doesn't really seem like the right place for those defines.
The patch instead defines those symbolic offsets in sysdeps.h,
in two variants for the old and new ABI, and uses them systematically
in all assembler files, not just the context routines.
The second change only affected a few assembler files that used
the save area to temporarily store some registers. In those
cases where this happens within a leaf function, this patch
changes the code to store those registers to the "red zone"
below the stack pointer. Otherwise, the functions already allocate
a stack frame, and the patch changes them to add extra space in
these frames as temporary space for the ELFv2 ABI.
2013-12-04 12:55:03 +00:00
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ld r2,FRAME_TOC_SAVE(r1)
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Call exit directly in clone (BZ #21512)
On aarch64, alpha, arm, hppa, mips, nios2, powerpc, sh, sparc, tile,
and x86_64 the clone syscall jumps to _exit after the child execution
and the function ends the process execution by calling exit_group.
This behavior have a small issue where threads created with
CLONE_THREAD using clone syscall directly will eventually exit the
whole group altogether instead of just the thread created. Also,
s390, microblaze, ia64, i386, and m68k differs by calling exit
syscall directly.
This patch changes all architectures to call the exit syscall
directly, as for s390, microblaze, ia64, i386, and m68k. This do not
have change glibc internal behavior in any sort, since the only
usage of clone implementation in posix_spawn calls _exit directly
in the created child (fork uses a direct call to clone).
Checked on x86_64-linux-gnu, i686-linux-gnu, aarch64-linux-gnu,
powerpc-linux-gnu, powerpc64le-linux-gnu, sparc64-linux-gnu,
and sparcv9-linux-gnu.
[BZ #21512]
* sysdeps/unix/sysv/linux/aarch64/clone.S (__clone): Call exit
syscall instead of jump to _exit.
(CLONE_VM_BIT): Remove unused define.
(CLONE_VM): Likewise.
(CLONE_THREAD_BIT): Likewise.
(CLONE_THREAD): Likewise.
* sysdeps/unix/sysv/linux/alpha/clone.S (__clone): Likewise.
(CLONE_VM): Remove unused define.
* sysdeps/unix/sysv/linux/arm/clone.S (__clone): Likewise.
(CLONE_VM): Remove unused define.
(CLONE_THREAD): Likewise.
* sysdeps/unix/sysv/linux/i386/clone.S (CLONE_VM): Likewise.
* sysdeps/unix/sysv/linux/ia64/clone2.S (__clone2): Call exit
syscall instead of jump to _exit.
* sysdeps/unix/sysv/linux/hppa/clone.S (__clone): Likewise.
* sysdeps/unix/sysv/linux/mips/clone.S (__clone): Likewise.
(CLONE_VM): Remove unused define.
(CLONE_THREAD): Likewise.
* sysdeps/unix/sysv/linux/nios2/clone.S (__clone): Likewise.
(CLONE_VM): Remove unused define.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/clone.S (__clone):
Likewise.
(CLONE_VM): Remove unused define.
(CLONE_THREAD): Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/clone.S (__clone):
Likewise.
(CLONE_VM): Remove unused define.
(CLONE_THREAD): Likewise.
* sysdeps/unix/sysv/linux/sh/clone.S (__clone): Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/clone.S (__clone): Likewise.
(CLONE_VM): Remove unused define.
* sysdeps/unix/sysv/linux/sparc/sparc64/clone.S (__clone): Likewise.
(CLONE_VM): Remove unused define.
* sysdeps/unix/sysv/linux/tile/clone.S (__clone): Likewise.
* sysdeps/unix/sysv/linux/x86_64/clone.S (__clone): Likewise.
(CLONE_VM): Remove unused define.
* sysdeps/unix/sysv/linux/Makefile (tests): Add tst-clone3.
* sysdeps/unix/sysv/linux/tst-clone3.c: New file.
Fix
2017-06-22 11:49:34 +00:00
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powerpc: Runtime selection between sc and scv for syscalls
Linux kernel v5.9 added support for system calls using the scv
instruction for POWER9 and later. The new codepath provides better
performance (see below) if compared to using sc. For the
foreseeable future, both sc and scv mechanisms will co-exist, so this
patch enables glibc to do a runtime check and use scv when it is
available.
Before issuing the system call to the kernel, we check hwcap2 in the TCB
for PPC_FEATURE2_SCV to see if scv is supported by the kernel. If not,
we fallback to sc and keep the old behavior.
The kernel implements a different error return convention for scv, so
when returning from a system call we need to handle the return value
differently depending on the instruction we used to enter the kernel.
For syscalls implemented in ASM, entry and exit are implemented by
different macros (PSEUDO and PSEUDO_RET, resp.), which may be used in
sequence (e.g. for templated syscalls) or with other instructions in
between (e.g. clone). To avoid accessing the TCB a second time on
PSEUDO_RET to check which instruction we used, the value read from
hwcap2 is cached on a non-volatile register.
This is not needed when using INTERNAL_SYSCALL macro, since entry and
exit are bundled into the same inline asm directive.
The dynamic loader may issue syscalls before the TCB has been setup
so it always uses sc with no extra checks. For the static case, there
is no compile-time way to determine if we are inside startup code,
so we also check the value of the thread pointer before effectively
accessing the TCB. For such situations in which the availability of
scv cannot be determined, sc is always used.
Support for scv in syscalls implemented in their own ASM file (clone and
vfork) will be added later. For now simply use sc as before.
Average performance over 1M calls for each syscall "type":
- stat: C wrapper calling INTERNAL_SYSCALL
- getpid: templated ASM syscall
- syscall: call to gettid using syscall function
Standard:
stat : 1.573445 us / ~3619 cycles
getpid : 0.164986 us / ~379 cycles
syscall : 0.162743 us / ~374 cycles
With scv:
stat : 1.537049 us / ~3535 cycles <~ -84 cycles / -2.32%
getpid : 0.109923 us / ~253 cycles <~ -126 cycles / -33.25%
syscall : 0.116410 us / ~268 cycles <~ -106 cycles / -28.34%
Tested on powerpc, powerpc64, powerpc64le (with and without scv)
Tested-by: Lucas A. M. Magalhães <lamm@linux.ibm.com>
Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
2020-12-03 17:15:27 +00:00
|
|
|
li r0,(SYS_ify(exit))
|
|
|
|
|
DO_CALL_SC
|
2010-08-12 16:19:19 +00:00
|
|
|
/* We won't ever get here but provide a nop so that the linker
|
|
|
|
|
will insert a toc adjusting stub if necessary. */
|
|
|
|
|
nop
|
2002-09-17 23:50:03 +00:00
|
|
|
|
2010-08-12 16:19:19 +00:00
|
|
|
L(badargs):
|
|
|
|
|
cfi_startproc
|
|
|
|
|
li r3,EINVAL
|
|
|
|
|
TAIL_CALL_SYSCALL_ERROR
|
|
|
|
|
|
2002-09-17 23:50:03 +00:00
|
|
|
L(parent):
|
2020-12-03 17:15:28 +00:00
|
|
|
/* Check if scv is available. */
|
|
|
|
|
cmpdi cr1,r28,0
|
|
|
|
|
|
2002-09-17 23:50:03 +00:00
|
|
|
/* Parent. Restore registers & return. */
|
2021-04-09 17:47:27 +00:00
|
|
|
#ifdef USE_PPC_SCV
|
2020-12-03 17:15:28 +00:00
|
|
|
cfi_offset(r28,-32)
|
2021-04-09 17:47:27 +00:00
|
|
|
ld r28,-32(r1)
|
|
|
|
|
cfi_restore(r28)
|
|
|
|
|
#endif
|
PowerPC64 ELFv2 ABI 4/6: Stack frame layout changes
This updates glibc for the changes in the ELFv2 relating to the
stack frame layout. These are described in more detail here:
http://gcc.gnu.org/ml/gcc-patches/2013-11/msg01149.html
http://gcc.gnu.org/ml/gcc-patches/2013-11/msg01146.html
Specifically, the "compiler and linker doublewords" were removed,
which has the effect that the save slot for the TOC register is
now at offset 24 rather than 40 to the stack pointer.
In addition, a function may now no longer necessarily assume that
its caller has set up a 64-byte register save area its use.
To address the first change, the patch goes through all assembler
files and replaces immediate offsets in instructions accessing the
ABI-defined stack slots by symbolic offsets. Those already were
defined in ucontext_i.sym and used in some of the context routines,
but that doesn't really seem like the right place for those defines.
The patch instead defines those symbolic offsets in sysdeps.h,
in two variants for the old and new ABI, and uses them systematically
in all assembler files, not just the context routines.
The second change only affected a few assembler files that used
the save area to temporarily store some registers. In those
cases where this happens within a leaf function, this patch
changes the code to store those registers to the "red zone"
below the stack pointer. Otherwise, the functions already allocate
a stack frame, and the patch changes them to add extra space in
these frames as temporary space for the ELFv2 ABI.
2013-12-04 12:55:03 +00:00
|
|
|
cfi_offset(r29,-24)
|
|
|
|
|
cfi_offset(r30,-16)
|
|
|
|
|
cfi_offset(r31,-8)
|
|
|
|
|
ld r29,-24(r1)
|
|
|
|
|
ld r30,-16(r1)
|
|
|
|
|
ld r31,-8(r1)
|
2010-08-12 16:19:19 +00:00
|
|
|
cfi_restore(r29)
|
|
|
|
|
cfi_restore(r30)
|
|
|
|
|
cfi_restore(r31)
|
2014-05-21 01:31:04 +00:00
|
|
|
|
2021-04-09 17:47:27 +00:00
|
|
|
#ifdef USE_PPC_SCV
|
2020-12-03 17:15:28 +00:00
|
|
|
beq cr1,0f
|
|
|
|
|
RET_SCV
|
|
|
|
|
b 1f
|
2021-04-09 17:47:27 +00:00
|
|
|
#endif
|
2020-12-03 17:15:28 +00:00
|
|
|
0: RET_SC
|
|
|
|
|
1: TAIL_CALL_SYSCALL_ERROR
|
|
|
|
|
|
2006-04-04 07:01:16 +00:00
|
|
|
|
2013-03-06 00:10:21 +00:00
|
|
|
END (__clone)
|
2002-09-17 23:50:03 +00:00
|
|
|
|
2016-01-19 19:33:32 +00:00
|
|
|
libc_hidden_def (__clone)
|
2013-03-06 00:10:21 +00:00
|
|
|
weak_alias (__clone, clone)
|
